56.5. Message Headers

unmarshal 操作会将来自 MSH 片段中的字段作为 Camel 消息上的标头添加：

键	MSH 字段	示例
`CamelHL7SendingApplication`	`MSH-3`	`MYSERVER`
`CamelHL7SendingFacility`	`MSH-4`	`MYSERVERAPP`
`CamelHL7ReceivingApplication`	`MSH-5`	`MYCLIENT`
`CamelHL7ReceivingFacility`	`MSH-6`	`MYCLIENTAPP`
`CamelHL7Timestamp`	`MSH-7`	`20071231235900`
`CamelHL7Security`	`MSH-8`	`null`
`CamelHL7MessageType`	`MSH-9-1`	`ADT`
`CamelHL7TriggerEvent`	`MSH-9-2`	`A01`
`CamelHL7MessageControl`	`MSH-10`	`1234`
`CamelHL7ProcessingId`	`MSH-11`	`P`
`CamelHL7VersionId`	`MSH-12`	`2.4`
`CamelHL7Context`	``	`包含用于解析消息`
`CamelHL7Charset`	`MSH-18`	`UNICODE UTF-8`

除 CamelHL7Context 以外的所有标头 都是 字符串类型。如果缺少标头值，则其值为 null。